Dissection of a DVD writer
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Ok, here is the ‘Victim’ a Sony DWD28Q 16x dual layer DVDwriter
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And the underside:
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Now remove the four Philips screws & void the warrantyseal ;-)
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. D- D; v8 }; B+ Z9 `2 ? `Now release the left hand PCB
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- a9 j9 O5 o/ G& LFirst release the zif as shown by pushing the brown bar tothe right
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Release the PCB retaining catch and lift the PCB upwards.# |! L1 q) S, R' Y
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7 `6 q' W, L% m/ HRelease two more zifs on the underside of the PCB
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Now you can see the optical assembly (riding on the twoslide rails)$ [% z8 Y, O* z$ s; |7 i
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# e6 Q% O/ B p; F. t: K- y4 WNow the brute force bit – detach the rails.
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And here is the liberated optical assy.4 ~- ~6 Q3 F# V; C) k& c+ b; i
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R a( V' [/ l; {2 n% r' }% wNow is a good time to short out the diodes to prevent staticdamage.
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Remove all screws.
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Then cut its flexi.
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Prise the write diode (the one you really want) to the rightto break the adhesive & cut flexi.
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The two laser diodes (DVD r/w on the left, CD r/w on theright)
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. h, R9 S9 V: ~8 a1 ENow you could glue a collimating lens to the diode ….
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$ U" N: M6 M6 HAnd using a prototype laser diode driver. (check my ebayauctions for production drivers)
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I have measured 60mW out t 100mA drive3 O+ _7 P. T8 ~- w; `3 H! }+ l
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7 F9 ^: q5 E: k7 d+ Q7 J/ X5 qA nice, well collimated spot.
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Scanning by hand, the laser is modulated by a 1kHz squarewave.& i! z& d6 S* I# a4 p7 y* N0 _
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For more info on the driver see the 1A laser diode driverpage Die4Drive. |
